diff --git a/VolumeManager.cpp b/VolumeManager.cpp
index 899dc23..3b229b7 100644
--- a/VolumeManager.cpp
+++ b/VolumeManager.cpp
@@ -559,7 +559,7 @@
         const char *fileName, const char *mountPoint, bool force) {
     if (!isMountpointMounted(mountPoint)) {
         SLOGE("Unmount request for %s when not mounted", id);
-        errno = EINVAL;
+        errno = ENOENT;
         return -1;
     }